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      18,000 BTU mini-split heat pump · SAK Series

      Star Air Kontrol SAK-18-24MS/220

      Very good cooling efficiency and average heating efficiency for a 18,000 BTU mini-split heat pump, and certified for cold climates.

      Ranks #107 of 465 18,000 BTU mini-splits for cooling efficiency, and costs about $438 a year to run in a mixed climate like Atlanta.

      SEER2
      23.7 Cooling efficiency over a season
      Very good · beats 72%
      HSPF2
      10.3 Heating efficiency over a season
      Average · beats 55%
      EER2
      13.5 Cooling efficiency on a 95°F day
      Very good · beats 74%
      Heat at 5°F
      12,600 BTU/h70% of its 47°F output
      Excellent · beats 91%

      A good fit if…

      • You want low cooling bills - its SEER2 beats 72% of mini-splits.
      • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 12,600 BTU/h at 5°F.
      • You want steady temperatures and quiet running - the compressor varies its speed.

      Think twice if…

      • You want the newest refrigerant - it uses R-410A, which is being phased down.

      Calculate my running cost

      Details

      Specifications18,000 BTU, R-410A
      General
      BrandStar Air Kontrol
      Also sold asMAXI AIR, DUCTLESSAIRE, QUEBEC VAIR
      Outdoor unit modelSAK-18-24MS/220
      SeriesSAK Series
      TypeMini-split heat pump
      Nominal size18,000 BTU
      CompressorVariable-speed units run longer at low powerContinuously variable
      RefrigerantR-410A
      Connected (smart) capableNo
      On the market sinceApril 28, 2024
      Last certifiedApril 17, 2026
      Cooling
      SEER2Seasonal efficiency, higher is better23.7 (range 23.7)
      EER2Efficiency at 95°F outdoors13.5
      Cooling capacity18,000 BTU/h
      Heating
      HSPF2Seasonal efficiency, higher is better10.3
      Capacity at 47°F18,000 BTU/h
      Capacity at 17°F14,000 BTU/h
      Capacity at 5°F12,600 BTU/h
      COP at 5°F2.0 = twice as efficient as a space heater2.39
      ENERGY STAR cold climateYes
      Heating output as it gets colder70% kept at 5°F

      Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with SAK-18-24MS/220 at the standard test temperatures, in BTU/h:

      Certified matchups1 indoor units

      The same outdoor unit scores differently with each indoor unit. Ask your installer for the AHRI reference number of the exact system you are quoted.

      Indoor unitSEER2EER2HSPF2Heat @5°FAHRI ref.
      SAK-18-24MS/220 · cold climate23.713.510.312,600211504107
      Same unit, other model numbers5

      These model numbers have exactly the same certified ratings and matchups as the Star Air Kontrol SAK-18-24MS/220: the same equipment under another brand, or a variant code for voltage, colour or market. Everything on this page applies to them.

      Yearly running cost in 10 large cities$359-$1,075

      At each state's average electricity price and the city's typical heating and cooling hours.

      Questions6
      What is the SEER2 rating of the Star Air Kontrol SAK-18-24MS/220?
      The Star Air Kontrol SAK-18-24MS/220 is rated at up to 23.7 SEER2 and 13.5 EER2 for cooling and up to 10.3 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with.
      Is the Star Air Kontrol SAK-18-24MS/220 good for cold climates?
      Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 12,600 BTU/h at 5°F with a COP of 2.39, so it is still 2.4 times as efficient as electric resistance heat at that temperature.
      How much does the Star Air Kontrol SAK-18-24MS/220 cost to run per year?
      At its rated efficiency it costs about $359-$1,075 a year in electricity in large U.S. cities, depending on climate and local rates - for example $458 in Phoenix and $911 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
      Is the Star Air Kontrol SAK-18-24MS/220 the same as the MAXI AIR YS21F-18HRDN1?
      Yes, as far as the certified ratings go. ENERGY STAR lists 6 model numbers with identical efficiency, capacity and matchups, which means the same outdoor unit sold under a different brand or with a minor variant code (voltage, colour or region). The full list is on this page.
      Which indoor units work with the Star Air Kontrol SAK-18-24MS/220?
      ENERGY STAR lists 1 certified combination for this outdoor unit. The highest-rated one uses SAK-18-24MS/220.
      What refrigerant does the Star Air Kontrol SAK-18-24MS/220 use?
      It uses R-410A. R-410A is being phased down under the EPA AIM Act, and new systems are moving to R-454B and R-32.

      Running cost and savings

      Pre-filled with this model. Pick your city and what you heat with today; everything else is optional.

      Heat pump $463/yrYou save $465/yrSee details ↓
      1. Where you live
      Adjust heating and cooling hours

      Filled in from your city's climate. Change them if you run the system much more or less than usual.

      2. The heat pump Star Air Kontrol SAK-18-24MS/220
      3. What it replaces
      4. Price replace the example with your quote
      Heat pump, per year
      $463
      Current system, per year
      $928
      You save per year
      $465
      Payback
      15.1 years
      Net after 10 years
      -$2,349

      Cooling $267Heating $196Electricity used: 2,894 kWhSaved vs. a minimum-efficiency heat pump: $249

      Estimates use the unit's rated SEER2 and HSPF2, full-load hours derived from NOAA 1991-2020 degree days, average residential electricity prices from the U.S. EIA (12 months to July 2026) and fuel prices from EIA (2025 for natural gas, week of 2026-10-05 for propane and heating oil). Very cold days that need backup heat are not modelled. Federal minimum for comparison: 14.3 SEER2 / 7.5 HSPF2.

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      Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of April 17, 2026. How we use the data.